3 files changed, 57 insertions, 0 deletions
diff --git a/doc/compile/README.md b/doc/compile/README.md
index 70fe88311..8928a0086 100644
--- a/doc/compile/README.md
+++ b/doc/compile/README.md
@@ -110,6 +110,34 @@ Configuration of the C compiler binary, flags and include paths.
 	  cc.compile_options = ...
 	end
 
+C Compiler has header searcher to detect installed library.
+
+If you need a include path of header file use ```search_header_path```:
+
+	# Searches ```iconv.h```.
+	# If found it will return include path of the header file.
+	# Otherwise it will return nil .
+	fail 'iconv.h not found' unless conf.cc.search_header_path 'iconv.h'
+
+If you need a full file name of header file use ```search_header```:
+
+	# Searches ```iconv.h```.
+	# If found it will return full path of the header file.
+	# Otherwise it will return nil .
+	iconv_h = conf.cc.search_header 'iconv.h'
+	print "iconv.h found: #{iconv_h}\n"
+
+Header searcher uses compiler's ```include_paths``` by default.
+When you are using GCC toolchain (including clang toolchain since its base is gcc toolchain)
+it will use compiler specific include paths too. (For example ```/usr/local/include```, ```/usr/include```)
+
+If you need a special header search paths define a singleton method ```header_search_paths``` to C compiler:
+
+	def conf.cc.header_search_paths
+		['/opt/local/include'] + include_paths
+	end
+
+
 ### Linker
 
 Configuration of the Linker binary, flags and library paths.
diff --git a/mrbgems/mruby-hash-ext/mrblib/hash.rb b/mrbgems/mruby-hash-ext/mrblib/hash.rb
index ce8fa3577..1ebc540e8 100644
--- a/mrbgems/mruby-hash-ext/mrblib/hash.rb
+++ b/mrbgems/mruby-hash-ext/mrblib/hash.rb
@@ -100,4 +100,24 @@ class Hash
     end 
     self
   end
+
+  ##
+  #  call-seq:
+  #     hash.flatten -> an_array
+  #     hash.flatten(level) -> an_array
+  #
+  #  Returns a new array that is a one-dimensional flattening of this
+  #  hash. That is, for every key or value that is an array, extract
+  #  its elements into the new array.  Unlike Array#flatten, this
+  #  method does not flatten recursively by default.  The optional
+  #  <i>level</i> argument determines the level of recursion to flatten.
+  #
+  #     a =  {1=> "one", 2 => [2,"two"], 3 => "three"}
+  #     a.flatten    # => [1, "one", 2, [2, "two"], 3, "three"]
+  #     a.flatten(2) # => [1, "one", 2, 2, "two", 3, "three"]
+  #
+
+  def flatten(level=1)
+    self.to_a.flatten(level)
+  end
 end
diff --git a/mrbgems/mruby-hash-ext/test/hash.rb b/mrbgems/mruby-hash-ext/test/hash.rb
index 4c7dbb217..7d8d66b4e 100644
--- a/mrbgems/mruby-hash-ext/test/hash.rb
+++ b/mrbgems/mruby-hash-ext/test/hash.rb
@@ -73,3 +73,12 @@ assert("Hash#delete_if") do
   }
   assert_equal(base.size, n)
 end
+
+assert("Hash#flatten") do
+  a =  {1=> "one", 2 => [2,"two"], 3 => [3, ["three"]]}
+  assert_equal [1, "one", 2, [2, "two"], 3, [3, ["three"]]], a.flatten
+  assert_equal [[1, "one"], [2, [2, "two"]], [3, [3, ["three"]]]], a.flatten(0)
+  assert_equal [1, "one", 2, [2, "two"], 3, [3, ["three"]]], a.flatten(1)
+  assert_equal [1, "one", 2, 2, "two", 3, 3, ["three"]], a.flatten(2)
+  assert_equal [1, "one", 2, 2, "two", 3, 3, "three"], a.flatten(3)
+end